Winterize with low point drains

[Flan]

First year with the camper going into winter. I notice it has a set of hot/cold low point drains out back and a drain on the fresh water tank. Is there still a need to blow out the lines if using the drains? I opened all the faucets to break vacuum, even opened the blowoff valve on the hot water heater to break vacuum in there. Am I ok to pour some rv antifreeze down the drains and call it good?
Thanks

[DutchmenSport]

I found my low point drains drain a very small amount of water (or anti-freeze). They don't drain from the bathroom. I've tested this by opening both hot and cold low point, let it drain till it finished, then closing them off again.

Then blow the lines and see what comes out. Actually, quite a lot, especially in the bathroom faucets and toilet.

What you need to do is blow your lines (or use antifreeze). After doing that, then open your low point and let whatever drain out.

You purchased a very expensive toy when you got your RV. Don't try to cut corners that may eventually cost you a LOT more than you ever imagine. Take the time and do it right. In the long run, you are saving yourself time and money. It so simple to blow or antifreeze your water lines, takes only 10 minutes, I just don't understand why anyone would want to take risks at what could be a very expensive and time consuming-frustrating repair come spring!

[K_Charles]

If you feel lucky, try it. I tried that years ago and then blew out the lines to see how much water was left. After that I always blew out the lines. For me antifreeze only goes in the traps and the pooper.

[ken56]

Yes, blow out the lines with your compressor set no higher than 40 psi. Elbows in the lines may not just drain fully with the low point drains plus there will be slack points in the lines that may not drain without help.

P traps on the sinks and shower will be fine with just pouring in the antifreeze. Remember to open the toilet flush valve and outside shower too. Some people get by with just blowing out the lines while others prefer to pump the antifreeze throughout the lines. Up to you on how comfortable you are on doing either.

Remember to bypass the water heater and drain it separately.